Known commercial power mowers are generally divided into three separate categories: self-propelled walk-behind mowers, ride-on mowers operated by a seated occupant, and stand-on mowers operated by a standing occupant.
For example, U.S. Pat. No. 4,920,733 discloses a typical walk-behind power mower. U.S. Pat. No. 5,865,020 discloses a typical ride-on mower where an operator sits on a seat during mower operation. U.S. Pat. Nos. 5,984,031, 5,964,082 and 5,507,138 disclose known stand-on mowers, each of these three patents hereby being incorporated herein by reference.
Deck lift systems for power mowers are also known in the art. For example, see the cutter deck lift system in U.S. Pat. No. 5,865,020, the disclosure of which is incorporated herein by reference. The mower or cutter deck is supported by a plurality of chains and a deck lift system enables the cutter deck to be raised and lowered in order to adjust the cutting height of the mower. Control arms (e.g., see reference numeral 40 in the ""020 patent) are utilized to control the lateral position or location of the cutter deck. Unfortunately, the control arms in the ""020 patent are rather long. Long control arms are needed in the ""020 system because the engine deck (upon which the engine is mounted behind the seat) does not move up/down along with the cutter deck during cutting height adjustment (i.e., the engine and engine deck remain fixed in place). Thus, the control arms are lengthy in order to reduce the amount of lateral movement of the cutter deck during raising/lowering operations in order to prevent large amounts of slack and/or tightness from building up in the pulley belt(s) which extend between the engine drive shaft and the blade pulleys mounted in top of the cutter deck. Unfortunately, long control arms means that the mower is more susceptible to damage caused by sideloads (e.g., when the side of the cutter deck is hit by something, or runs into an object such as a curb or tree).
Accordingly, it will be apparent to those skilled in the art that there exists a need in the art for a power mower deck lift system that can be designed so as to enable the efficient use of short control arms without overcomplicating the design of the mower. However, when shorter control arms are utilized, this results in a greater degree of angular pivoting by the control arms which in turn causes the deck assembly to move further in the forward/rearward directions during raising and lowering of the deck assembly. Accordingly, it will be apparent to those skilled in the art that there also exists a need in the art for a tractor frame structure than can accommodate the degree of forward/rearward movement by the deck assembly resulting from shorter control arms. It is an object of this invention to fulfill this and other needs which will become apparent to the skilled artisan from reading the instant disclosure.
An object of this invention is to provide a deck lift system on a mower wherein control arms can be made short in length so as to make the mower more resistant to damage caused by sideload impact(s) on the cutter deck.
Another object of this invention is to provide a tractor frame structure for use in a power mower, wherein the tractor frame structure is designed so as to accommodate additional forward/rearward movement of the cutter deck assembly due to shorter control arms.
Another object of this invention is to provide a tractor frame for use in a power mower, wherein the tractor frame includes a pair or approximately parallel sidewalls with a cross member extending therebetween.
Another object of this invention is to provide a deck lift system on a mower wherein the cutter and engine deck assemblies (including the engine) are raised and lowered together as one unit when adjusting the blade cutting height of the mower.
Another object of this invention is to provide a power mower where the operator is capable of standing or sitting during different modes of mower operation.
Another object of this invention is to provide a mower where the battery(ies) can be located between feet of an operator in order to lower the overall center of gravity of the mower.
Another object of this invention is to provide a depression area at a rear portion of a cutter deck assembly so that a clutch above the depression may extend further downward than would otherwise be possible. This enables the engine to be located further forward at the same elevation than if the depression were not present.
Another object of this invention is to provide a mower designed so that when going up a hill a mower operator can move from a sitting position to a standing position so that the overall center of gravity of the mower can be moved forward to minimize potential for tipping backward.
Another object of this invention is to provide a seat assembly which enables an operator to easily jump off of or abandon the machine.
Another object of this invention is to provide a seat on a mower, where the seat may be folded up into a storage or stowed position when the operator is standing on the mower or when there is a desire to transport or store the mower.
Another object of this invention is to provide a mower including a seat structure which is both comfortable and may be efficiently moved between deployed and non-deployed positions.
Another object of this invention is to provide a deck lift system which lifts an engine deck and a cutter deck together with one another, so that control arms utilized for positioning the deck can be designed to be shorter thereby enabling the deck assembly to be more resistant to negative impacts which may be caused by sideloads.
Yet another object of this invention is to satisfy or fulfill one or more of the above listed objects.
Certain embodiments of this invention fulfill one or more of the above-listed objects or needs by providing a self-propelled power lawn mower comprising:
first and second rear drive wheels that are independently driveable so as to enable the mower to conduct approximate zero radius turns about a zero radius turning axis;
a foot platform for supporting at least one foot of an operator of the mower, said foot platform being located at an elevation less than an elevation of a top edge of at least one of said rear drive wheels;
a deck lift system for raising and lowering a cutter deck assembly, an engine deck, and an engine together as one unit in order to adjust a blade cutting height of the mower;
a seat for supporting an operator in a sitting position; and
a tractor frame for supporting the foot platform and the seat, said tractor frame including first and second approximately parallel sidewalls and a cross wall member extending between said first and second sidewalls.
Certain embodiments of this invention further fulfill one or more of the above-listed needs by providing a power lawn mower comprising:
a deck lift system for raising and lowering a cutter deck assembly, an engine deck, and an engine in adjusting a blade cutting height of the mower;
a tractor frame for supporting at least one of a foot platform and a seat, said tractor frame including first and second approximately parallel sidewalls and a cross wall member extending between said first and second sidewalls; and
wherein said cross wall is curved or shaped in a manner so that toes of an operator""s feet are on a first side of the cross wall and the engine deck is on a second side of the cross wall, and wherein at least a portion of the engine deck moves upward and downward on the second side of the cross wall at a location vertically above the toes of the operator""s feet.
In still further embodiments of this invention, one or more of the above-listed objects and/or needs are fulfilled by providing a power mower comprising:
a cutter deck;
an engine including a clutch, wherein a drive shaft extends downward from said engine;
said cutter deck including a top surface and at least one sidewall which form a right angle with one another around a significant portion of a periphery of said cutter deck; and
a depression formed in said cutter deck at a rear portion thereof, said depression being formed by a plate or sheet extending at an angle between said top surface of said cutter deck and said sidewall of said cutter deck at a location wherein said top surface and sidewall do not form a right angle with one another.